This invention generally relates to active noise cancellation in a vehicle induction system. More particularly, this invention relates to active noise cancellation providing a selectable engine noise profile.
Moderm day vehicles typically include an air induction system. One drawback of air induction systems is that engine noise frequently travels through the air induction system and emanates out of the mouth of the air intake such that the noises are noticeable in the passenger compartment of the vehicle. Various efforts have been made to reduce the amount of engine noise traveling through the air induction system. Some arrangements include passive devices such as expansion chambers and Helmholtz resonators. Other efforts include active methods such as anti-noise generators.
Typical active systems include a speaker that generates a sound to attenuate engine noise. The sound from the speaker is typically out of phase with the engine noise and combines with the engine noise. The result is a reduced noise in the air induction system, which results in less noise transmission into the passenger compartment.
Most active noise cancellation systems are preset by a vehicle manufacturer or supplier to achieve a desired amount of noise reduction. The choice for setting the active noise cancellation system is typically made by one or more technicians utilizing a test vehicle having a lap top computer, for example, appropriately coupled with the controller of the test vehicle active noise cancellation system. The technician is able to interface with the active noise system controller to adjust the performance of the active noise system as needed. This process provides a standard for presetting similar systems. Such settings are typically preprogrammed into the controllers of active noise cancellations systems subsequently provided to customers.
The eventual customer or vehicle owner is unable to adjust the performance of the active noise cancellation system. This invention provides an enhanced feature recognizing that some individuals may desire to customize the performance of the active noise cancellation system to achieve a desired engine noise profile.